把某一段导线均匀拉至原来的两倍，则其阻值（）
A、变为原来阻值的两倍
B、变为原来阻值4倍
C、变为原来阻值的二分之一
D、不变
参考答案：B
________the variety that the average family has in beef, fish, poultry, and vegetarian recipes, they find most meals unexciting.
A．In spite
B．Inspite
C．Despite of
D．Despite
火现场发现伤员有严重的前臂出血，应立即用指压动脉法按压（）以迅速止血。
A.股动脉
B.肱动脉
C.颈动脉
